Atop the UT Tower stands a magnificent
clock that keeps the entire campus running on schedule.
The four faces of the clock are 12 feet in diameter and
are trimmed in gold leaf. Installed in 1936, the hands of
the clock were so shiny that people had difficulty seeing
the time!

Today, the clock can be seen from most places
on campus. The mechanism that controls the time displayed at the
Tower is the same mechanism that controls almost all clocks on
campus. Strange as it may seem, UT time originates in the
Service Building. There are two grand-master clocks located in
the Service Building. One grand-master controls campus clocks
made by IBM, which are mostly located in the older buildings. IBM
clocks do not have hands that measure seconds. The other
grand-master controls the Simplex clocks in the newer buildings.
Each building on campus houses a clock sub-master, which is
linked by telephone wires to one of the grand-masters. Behind
most building clocks on campus are wires, not gears.

Unlike other buildings on campus, the Main
Building has two sub-masters connected to the IBM grand-master.
One sub-master controls the wall clocks in Main; the other
controls the Tower clock. The Tower sub-master transmits pulses
to the clock housing at the top of the Tower. In the clock
housing, a set of weights on chains provides stored energy that
actually operates the clock. Each pulse from the sub-master
causes a weight to drop a fraction of an inch. Each weight is
connected to a gear that moves the hands on the clock faces. Once
the weights reach the floor, an electric motor pulls them to the
top of the chain to start the process again.

Before using the two grand-master
clocks, UT kept time according to WWV, the National
Bureau of Standards short-wave radio station in Fort
Collins, Colorado. WWV sent radio signals to a master
clock located in the Student Services Building. The
master clock converted the radio signals into pulses that
were then transmitted over telephone wires to two
sub-masters in the basement of the Tower. UT stopped
using signals from WWV in the 1980s due to continual
interference which prevented the master clock from
receiving the signal reliably. In the future, UT may use
WWVs signals again, or use a global positioning
satellite to keep accurate time on campus.